The filtration of drinking water in general makes use of a water filter cylinder filled with filter material (such as active carbon or ion-exchange resin or other various filter materials) so as to separate and adhere solid impurity in the water.
The drinking water in the water inlet pipe (port) of water filter is filtered through natural or chemical fiber cloth or foaming filtration so as to eliminate larger solid impurity in the water, then enters into the water filter cylinder filled with filter material and small solid impurity is adhered by active carbon or ion-exchange resin or other various filter materials, finally the filtered and clean water is drained from the water outlet pipe (port) for drinking.
In the foregoing course, the larger solid impurity in the drinking water gradually accumulates in a filtration layer of water inlet pipe (port) and the dirt in water tends to block the filtration layer to decrease effectiveness of filtration. Therefore, manufacturers adopt a way of flowing water adversely to flush the filtration layer and eliminate said dirt. One of the examples is Taiwan Application No. 80203471 titled "An Adversely Flushed Water Filter" of Mr. Tzu-Fu Lin.
However, it is very difficult for the flushing force of flowing water adversely to effectively cleanse the dirt adhered to the filtration layer for a long time. It is proved that we have to manually use a brush or a detergent and a sterilizing medicine to forcefully wash and brush the dirt to cleanse a water tower in general, so the filter material of invention of adversely flushed water filter of Mr. Tzu-Fu Lin needs to be replaced after it is actually used for more than six months so as to keep its healthiness.
In the foregoing filtration course of drinking water in general, the water is filtered through the filtration layer in the water inlet pipe (port), then through the filter material in the water filter cylinder which adheres to smaller solid impurity in the water depending on the direction, course and speed of water flowing. The longer the water flow course and the slower the water flow speed, the higher the rate of filter material adhered to the smaller solid impurity in water, and the better the effectiveness of cleansing the drinking water.